Can sorting machine



A ril 8, 1952 H. J. EMERSON ETAL CAN SORTING MACHINE 2 SHEETS-SHEET 1 Filed Jan. 19, 1949 N m w wRwmm (71M R0 E 1 /.R N WVM 1 O N N 1 MOE n .C 1 W A HEM W mmR. FM W M Y O 0 G B HR April 1952 H. J. EMERSON ETAL CAN SORTING MACHINE 2 SHEETSSHEET 2 Filed Jan. 19, 1949 FIG.3.

FIG. 5.

g m m mm H m M WPOVEI f E A m W www W HR Patented Apr. 8, 1952 'fNilTE D SS'TATES PATENT OFFICE "CAN ISORTING MACHINE Howard J. Emerson, Robert J. 'OConnor, and

"George :A. Emery, Rochester, N, Ye, assignors -to Eastman Kodak Company, Rochester, N. 1 ,a corporation of 'New Jersey Application January 19, 1949, S'eriaINoJHfilZ (01. coo-L81) lzGlaims.

This invention relates to a can sorting machine and more specifically to :a machine .adapted to the identification and sorting out .of improperly la- "beled cans.

It has been found, where cans of :the same size having difieren't labels lithographed thereon are used to package the different materials or substances "identified by such labels, that on oo-- casion oans designated as containing a certain substance are improperly filled with another. This results "from cans halving different-labels becoming 'mixed together and not being readily discerned by the operator or the machine used tofi ll and seal the cans because "of the identity of size and "shape of the cans and often because of the s'imila-rity of the ii thographed markings on the cans themselves. The present invention :is directed "to the provision of an apparatus which is entirely independent of the personal element and which will positively identify and reie'ct such cans whose labels diner from those of the cans intended to be filled with :a particular substance. This is =accomp1ished by the use of code marks which are formed on theoan surface at the same time that the surface is being l-lithographed with its designation. 'Thcsemarks comprise .a pair or small exposed areas of :meta'] whose position upon the cylindrical can surface corresponds "to :a particular can label. The apparatus embodying the present invention is adapted to ii'dentifyby electrical means cans having the desired code imark- *in'gs and reject all those not so marked. The apparatus is positive in its operation. Only cans having the :proper code markings-will produce the signal which will operate the means which accepts the cans, thus providing for failure of the equipment which will automatically resultin all cans being rejected. The apparatus is so designed that an impulse caused by :poorly lithographed cans or improper passage .of the pans through the machine will not function to operate the machine to accept such cans. Only an impulse of definite amplitude and duration will opierat'e themechanism.

It'is, therefore, an object of the present :inven tion provide an improved apparatus which :is adapted to identify and sort out improperly riabeled cans.

It is a further object of this invention to provide an apparatus of this kind which is positive in its operation in accepting properly coded cans, rejecting all others.

It is a still further object of this invention to provide an apparatus of the class described which is adapted to be used with cans having .2 code marks thereon comprising :small'exposed metalareas.

:It is a still further object of this invention to provide an improved apparatus which is adapted to identify and accept, through the functioning of ail-electric signal, properly :labeled cans.

It sisa 'still'iurt-her object of this invention to provide an apparatus :of :the class described which :may be .readily:modified for the identification :of nans. 'having different code marks.

It is a still further object :of this invention to provide a. can sorting apparatus :of the -class described which is relatively simple in its construction :and foolproof in its operation.

Other (objects and "advantages :of the invention :will become apparent from the following description taken :in connection with the accompanying drawings, and ,it will be understood that many changes may he made in the :details of constructions and arrangement .Of parts vshown and described without departing :from the spirit of the invention as expressed in ith'e accompanylug-claims. We, therefore, do not wish to be limited te-the exact details shown and described as the preferred form sonlyghas 'been shown byway #of illustration.

ln'theedr'awings':

Fig. ;1 is a plan'view of :a can identification and sorting apparatus embodying the present :inven Jtlon';

Fig. 2 .is a :side elevational view offthe apparatus of Fig. .1'; I

Fig. '3 :is :a sectionarvi'ewni theapparatus :taken =on-Ith'e line33pf Fig.2;

Fig. 4 is a perspective view of a can sucharsis intended to be sorted z-by the herein described Japp'aratumand Rig. 5 .:is :a wiring diagram illustrating :the :elecztrieal circuit and zconnectionsiby which the sig- .na;l:is generated tor the .identiiicationzand accepting ofaproperlycodedcan.

Y In the apparatus illustrated (in :Figs. '1 to cans it!) fancied. one "by one, into the apparatus between the :belts 1H and the contact bars 12. The gbelts H serve :a dual purpose. E-Ifhey hold the cylindrical surface of each can in intimate contact with the bars 1.2 :and, secondly, propel the :can through the apparatus by telling .it along :the said fears. Each belt -41 .01 "which :there are preferablytwo is driven between :a pair of pulleys 413 and 1 4. The pulleys 14 are freely rotatable upon a verticalshaft I 5, while the pulleys are fixed to the vertical shaft :I'B which is :rotated through ithe medium of the pulley :cl'r'l' and the drive :belt fll. The :belt sl8 itself .driven by means of a pulley 19 connected through conventional gear reduction means 20 with the motor 2|. The belts H are themselves sufiiciently resilient and so spaced from the contact bars 12 that a can thrust therebetween is readily grasped and rolled along in contact with the bars, until it emerges at the other end into the chute 22.

The contact bars l2 constitute elongated electrical contacts which extend somewhat less than the length of the belts ll. While seven such bars are illustrated, the contact of only two bars with the two code marks 3| on a can serves to identify a particular can. By using seven bars, however, twenty-one difierent combinations of pairs of bars are possible and the apparatus may thus be employed to identify twenty-one different codes merely by varying the electrical connections to the bars, as will be clearly understood from the description of the electrical circuit and its operation which is given below. The bars 12 are preferably made of stainless steel rather than copper because of the formers greater resistance to wear and the much smaller likelihood of its corroding. These bars are mounted at each end in slots formed in the upright supports 23, which themselves are made of a nonconducting material to insulate the bars from each other. To provide a more positive contact between each of the bars l2 and the can H], the bars may be loosely mounted in the slots in the supports 23, there being small rubber inserts in the bottom of the slots to resiliently press each bar into intimate contact with the can. The use of such a feature will permit the bars to be made and mounted within less exacting tolerances and will also provide the requisite contact between bars and can despite small deformations in the latter. The supports 23, like the pulley shafts, gear reduction means, motor, etc. are mounted securely upon the supporting frame 24.

Each can after emerging from between the belts and the contact bars travels along the chute 22 and, if not identified as a properly coded can, will continue therealong to a discard receptacle (not shown). However, if properly coded, a can will in passing between the belts and bars cause the electrical circuit to generate a signal, as will be described below, which signal will cause the solenoid 25 to swing a gate 26 by means of the lever mechanism 21 into the path of the chute, thereby deflecting the can therefrom into a second path or chute 28. The latter leads to a bin or receptacle (not shown) which receives the properly coded and, therefore, correctly labeled cans.

The electrical circuit, which is employed to provide the signal when a properly coded and labeled can is passed through the above-described apparatus, includes two direct current voltage sources 29 and 30 which are connected in opposition and. being of equal potential, ordinarily have no effeet in the circuit. The two bars which are to serve to identify a particular can are connected across the source ofvoltage 30. For purposes of illustration, the two lowermost of the seven bars I2 in Fig. are so connected and will, upon contacting the code marks 3|, produce the signal which will actuate the solenoid 25 to cause it to swing the gate 26 across the path of chute 22 to bypass the can into chute 28. The remaining five bars are connected together and with one of the two bars connected across voltage source 30 are connected across voltage source 29 as shown in Fig. 5. The above-described signal will only be generated when the grid-controlled rectifier 33 is conducting but this is prevented by the small negative voltage impressed upon the rectifier grid by the battery 32. However, when a can having code marks 3|, which are adapted to contact the lowermost pair of bars l2, passes through the apparatus. the can will short out voltage source 30 upon contact being made between the code marks and the bars. This upsets the balance of the two voltage sources 29 and 30 and, since each of the latter is of higher potential than battery 32. a resultant positive voltage is impressed upon the grid of the rectifier tube 33 with the result that the tube begins to conduct the current generated by battery or voltage source 34, the latter producing a considerably higher potential than battery 32. This closes the relay 35 which, in turn, closes the solenoid circuit (not shown) and the solenoid 25, thus actuated, swings gate 26 into chute 22 to divert the can into the path 28.

In order that the relay 35 will be held closed for a period long enough to enable the can to continue along the bars and finally pass through the gate 26, an adjustable time delay is built into the rectifier circuit. The adjustable time delay means comprises the condenser 36, the variable resistance 31 and the gaseous discharge tube 38. The code marks 3| having made and then broken contact with the pair of bars [2, the gas-filled, rectifier tube 33 continues to conduct the current in the relay circuit. How long the relay will remain closed will depend upon the electrical values of the condenser 36, the resistance 31 and the gaseous discharge tube 38. When conduction of the rectifier 33 first begins, the current of the relay circuit starts charging condenser 36 through the variable resistance 31. When the critical breakdown voltage of the gaseous discharge tube 38 is reached, the condenser 36 discharges therethrough, thus momentarily dropping the plate voltage of rectifier 33 to zero which extinguishes the rectifier to open up the relay. The time elapsed between the first contact of the code marks 3| and the bars I2 and the dropping out or opening of the relay 35 will be at least as great, and preferably somewhat greater, than the time required for the can to continue along the bars after making the said contact, pass along the chute 22 and through the gate 26. The time that elapses between the closing and opening or the relay can, of course, be varied by manipulation of the adjustable resistance 31.

To prevent accidental firing or the conduction of the tube 33 several precautions are taken. It is possible that poorly lithographed or coded, or deformed cans, or the improper passage of the cans through the apparatus may cause a momentary signal voltage to be impressed upon the grid of the tube 33. To avoid firing of the tube under such circumstances, a parallel condenser 39 is incorporated in the circuit to resist any sudden, momentary change from negative to positive of the voltage impressed upon the grid of tube 33. The capacity value of 39 will determine of what duration and amplitude an impulse must be to operate the apparatus; A second precaution taken is the use of two grounding bars 4!], one of which is mounted in each of the upright supports 23. These bars are so positioned that each overlaps the ends of the contact bars [2, as noted in Figs. 1 and 2. These, too, serve to prevent transient voltages and possible resulting signals, which might otherwise occur under such as the following conditions.

When a can first comes into contact with the 3' bars I2, it is possible that the vertical strip .01

, exposed metal 44, which "includes the seam or solder joint 41 as seen in Fig. 4,-will be the portion of 'the'peripheral surface of the can, rather than the lithographed area '42, to first contact the ends of the bars. Due to the difficulty of properly aligning the ends of the bars, especially if these arespring pressed or mounted-on'rubber inserts as discussed above, it is very possible that the exposed metalstrip -may make instantaneousscontact with-only :a few of the :bars. Depending upon the particular connection of these fewbars within the electrical circuit, this can .well :result in transient voltages in the circuit, 'causingthe grid controlled :rectifier 33 to begin conducting. One grounding bar to :is so positioned, however, that the cans are caused to contact it just prior to engaging the plurality of :contact bars. Thus, any :voltage diiierent-ial across "a :can. caused by the vertical strip or seam of ithe cannot making instantaneous contact with all the contact bars, is grounded out by :the bar ll! through the circuit as shown in Fig.5. .-In like manner, a second grounding bar 40 is positioned in overlapping relation with the other ends of the plurality of bars I2 to preclude a similar effect occasioned by the vertical seam of the can ,passingover the ends of the bars as the can leaves the bars. Here the grounding bar 40 extends beyond the ends of the contact bars l-2 to-ground out improper voltage differentials across the can, as in the first instance.

No specific electrical values are given for the various elements shown in Fig. 5 for these are interrelated and may be readily determined by one skilled in the art. Some will depend upon the .physica'l dimensions of the apparatus; thus, the values of the elements of the time delay means will depend upon the distance between the contact bars and the gate. A number of variable resistances have been incorporated in 'thecircuit, too, for purposes of adjustment as will be obvious to those skilled in the art. While we have depicted in the wiring diagram the several voltage sources "as batteries, obviously, any source of direct current potential is satisfactory; such voltages may, in fact, beprovide'd from a single source of alternating current by the use of suitable transformers and rectifiers.

The apparatus, described herein, is intended for use with cans having any type of coating or covering thereon, comprising the label, which is non-conducting and through which the metallic surface of the can may .be exposed to provide :a pair of code markings. Preferably such cans will be of the lithographed variety, the

'label being printed or impressed directly upon the can and completely encircling the periphery exceptior the narrow strip in which the joint occurs. When theplurality of bars l2 pass over this strip of exposed metal, the voltage of both batteries 29 and 30 are shorted through the can, the -resultant voltage of 29 and 30 is stillzero, and :no signal is produced to operate the gate '26. {Only when the single battery '30 is shorted, through contact .of the code marks with the pair of bars connected across battery 30, is an adequate signal given which will operate the gate. The cans should be fed past the bars one at a time in order that conflicting signals may .notbegiven. We have found that'the cans are best assorted after they are filled and sealed, since these offer greater "resistance to deformation caused by the pressure exerted on them by the bars I2 and "belts H. Moreover, the cans, emerging "at regular intervals from the sealing machine, automatically provides the proper 6 spacing to preclude more than a single man passing along the bars at one time. However, the apparatus is well adapted to the identificaion and sorting-of cans prior to their being ifllled to insure that only cans :properly labeled :are iedfinto "the filling machine.

While the wiring shown in Fig. 5 is intende for the identification of cans having :code marks adapted "to make contact with the lowermost pair of bars 1L2, any twoof the plurality not bars :may be connected across the battery 39 to identify cans having code marks which will-coincide with these two bars, the remaining five .bars bein connected :as a unit to the positive terminal of battery '29. "The apparatus, herein :described, may also 'be readily adapted for use with cans of different sizes. accomplished -by making the contact bar assembly' and the belt and drive mechanism -relatively movable in order "that the distance -between the "belts- H and the bars l2 may be varied to accommodate cans of diherent diameters. While we have :described the operation of the gate being effected by :a solenoid, other electrically actuated means, known to thoseskilled in the art, for converting the signal to a'physical "sorting of the cans may be employed in accordance with this invention. From the foregoing description, it will be apparent that we have provided means for obtainin'g all of the objects and advantages of this invention. v

What we claim and desire -to secure by Letters Patentof the United States is:

1. A "sorting machine for cans having a pair of exposed meta-l areas or code marks on the surface thereof comprising a "plurality of contacts, means for moving said cans across the plurality of contacts, a gate movable into the "path oi the cans beyond said plurality of contacts to divert the cans from said path, electrically actuated means for movingthe gate into the path, an electrical circuit connecting the electrically actuated -means to the plurality of contacts, two sources of voltage in said circuit, the voltages "being "in opposition and balanced to ordinarily have no effect upon the electrically actuated means, two of said contacts being connected across one of the voltage sources, the rema'inder of the contacts and one of said two contacts -be'in gconnected across the other voltage source, whereby, when said two contacts simultaneously make contact with the code areas of a can, the one source of voltage is shorted through the can, thereby "unbalancing the --'opposed voltages to operate the electrically actu ated means whereby the gate is moved 'todivert the can from said-path.

"2. "A sorting machine for cans having a pair of exposed metal areas or code marks on the sur- .iace thereof comprising a plurality of contacts, .means for rolling said cans -across 'the plurality of contacts, a gate movable into the path of the cans .at a point beyond said plurality of contacts to divert the cans from said path, electromagarctic means adapted to move the gate into the path, :an electrical circuit connecting the electromagnetic means to the plurality of contacts, two :sources of voltage in said circuit, the voltages being :in :opposition and balanced to ordinarily cause no signal whereby the electromagnetic means :is not efi'ected thereby, two of said con- Ztactsbeing connected across -.one of the voltage sources, the remainder of the contacts andone mi said two :contacts being connected across the other voltage sourge. whereby, when saidtwo contacts simultaneously make contact with the code areas of a can, the one source of voltage is shorted through the can, thereby unbalancing the opposed voltages to cause a signal which opcrates the electromagnetic means whereby the gate is moved to divert the can from said path, and means in said electrical circuit adapted to allow only a variation of a predetermined minimum amplitpude and duration in the net potential of the opposed voltages to cause a signal.

3. A sorting machine for cans having a Pair of exposed metal areas or code marks on the surface thereof comprising a plurality of elongated contacts, means for rolling said cans longitudinally along the plurality of contacts, a gate movable into the path ofthe cans at a point beyond said plurality-of contacts to divert the cans from said path into a second path, electromagnetic means adapted to move the gate into the path, an electrical circuit connecting the electromagnetic means to the plurality of contacts, two sources of voltage in said circuit, the voltages being in opposition and balanced to ordinarily provide no signal to actuate the electromagnetic means, two of said contacts being connected across one of the voltage sources, the remainder of the contacts and one of said two contacts being connected across the other voltage source, whereby, when said two contacts simultaneously engage the code areas of a can, the one source of voltage is shorted through the can, thereby unbalancing the opposed voltages to provide a signal capable of actuating the electromagnetic means whereby the gate is moved to divert the can into said second path, and time delay means in said electrical circuit to continue said actuation of the electromagnetic means after contact between the elongated contacts and code areas is broken for a period of sufficient duration to enable the can which has caused the signal to pass said gate into said second path.

4. A sorting machine for cans having a pair of exposed metal areas or code marks on the surface thereof comprising a plurality of parallel contact bars, a driven belt adapted to roll said cans lengthwise along the contact bars, means for conducting the cans along a predetermined path beyond the ends of said contact bars, a gate movable into the path of the cans at a point beyond the contact bars to divert the cans from said path, electromagnetic means adapted to move the gate intothe path, an electrical circuit connecting the electromagnetic means to the contact bars, two sources of voltage in said circuit, the voltages being in opposition and balanced to ordinarily cause nosignal to actuate the electromagnetic means, two of said contacts being connected across one of the voltage sources, the remainder of the contacts and one of said two contacts being connected across the other voltage source, whereby, when said two contacts simultaneously engage the code areas of a can, the one source of voltage is shorted through the can, thereby unbalancing the opposed voltages to cause a signal which actuates the electromagnetic means which moves the said gate into the path of the can. means in said electrical circuit adapted to allow only a variation of a predetermined minimum amplitude and duration in the net potential of the opposed voltages to cause a signal, and time delay means in said circuit to continue said actuation of the electromagnetic means after contact between the contact bars and code areas is broken for a period of sufiicient duration to enable the can which has caused the signal to be diverted by said gate.

iii;

5. A sorting machine for cans having a pair of exposed metal areas or code marks on the surface thereof comprising a plurality of parallel contact bars, a pair of driven belts spaced from said bars and adapted to roll said cans lengthwise along and in contact with said bars, a chute for conducting the cans along a predetermined path beyond the ends of the contact bars, a gate movable acrossthe chute to divert cans therefrom into a second path, a solenoid adapted to operate the gate, an electrical circuit interconnecting the solenoid and the contact bars, two sources of voltage in said circuit, the voltages being in opposition and balanced to ordinarily produce no signal capable of actuating the solenoid, two of said contact bars being connected across one of the voltage sources, the remainder of the contact bars and one of said two contact bars being connected across the other voltage source, whereby, when said two contact bars simultaneously engage the code areas of a can, the one source of voltage is shorted through the can, thereby unbalancing the opposed voltages to produce a signal capable of actuating the solenoid which moves the gate to divert the can from'said chute into said second path.

6. A sorting machine for cans having a pair of exposed metal areas or code marks on the surface thereof comprising a plurality of contacts, means for moving said cans across the plurality of contacts, electrically actuated means beyond said plurality of contacts adapted to se lectively direct each can into one of two paths, an electrical circuit connecting the electrically actuated means to the plurality of contacts, two sources of voltage in said circuit, the voltages being in opposition and balanced to ordinarily provide no signal which is capable of effecting said electrically actuated means, two of said contacts being connected across one of the voltage sources, the remainder of the contacts and one of said two contacts being connected across the other voltage source, whereby, when said two contacts simultaneously make contact with the code areas of a can, the one source of voltage is shorted through the can, thereby unbalancing the opposed voltages to provide a signal which eifects the electrically actuated means to direct the can into one of said two paths.

7. A sorting machine for cans having a pair of exposed metal areas or code marks on the surface thereof comprising a plurality of contact bars, means for rolling said cans longitudinally along the plurality of bars, a gate movable into the path of the cans at a point beyond said plurality of contact bars to divert the cans from said path into a second path, electrically actuated means adapted to move the gate into the path, an electrical circuit capable of providing a signal which will effect said electrically actuated means, said circuit including a pair of sources of voltage connected in opposition and so balanced as to preclude said circuit from ordinarily providing said signal, a connection from the negative ter minal of both voltage sources to one of said contact bars, a connection from the positive terminal of one of said voltage sources to a second contact bar, and a connection from the positive terminal of the second voltage source to the remainder of the contact bars, whereby, when said first two bars engage the code areas of a can. one source of voltage will be shorted through the can, thereby unbalancing the opposed voltages in said circuit to provide the signal effecting the electrically actuated means whereby the gate is moved to divert the can into said second path.

8. A sorting machine for cans according to claim 7 in which a timedelay means is included in said circuit, comprising a condenser and gaseous discharge tube, to continue said signal, after contact between the bars and code areas is broken, for a period of sufiicient duration to enable the can which has caused the signal to pass said gate into said second path.

9. A sorting machine for cans having a pair of exposing metal areas or code marks on the surface thereof comprising a plurality of contact bars, means for rolling said cans longitudinally along the plurality of bars, a gate movable into the path of the cans at a point beyond said plurality of contact bars to divert the cans from said path into a second path, electromagnetic means adapted to move the gate into the path, an electronic circuit including a grid-controlled rectifier which is adapted to produce a signal which will actuate the electromagnetic means when a voltage of correct polarity is impressed upon the grid of the rectifier, a pair of sources of voltage in the grid circuit which are in opposition and so balanced as to preclude the electronic circuit producing said signal, a connection from the negative terminal of both voltage sources to one of said contact bars, a connection from the positive terminal of one of said voltage sources to a second contact bar, and a connection from the positive terminal of the second voltage source to the remainder of the contact bars, whereby, when said first two bars engage the code areas of a can, one source of voltage will be shorted through the can, thereby unbalancing the opposed voltages to impress a voltage of correct polarity upon the rectifier grid whereby a signal will be given to actuate the electromagnetic means to move the gate and divert the can into said second path.

10. A sorting machine for cans according to claim 9 in which a time delay means is included in said electronic circuit, adapted to continue the signal to continue actuation of the electromagnetic means, after the contact between the bars and the code areas is broken, for a period of suflicient duration to enable the can which has caused the signal to pass and be diverted by the gate.

11. A sorting machine for cans according to claim 10 in which means is included in the grid circuit, adapted to allow only a variation 01 a 10 predetermined minimum amplitude and duration in the net potential of the opposed voltages to cause the electronic circuit to produce said signal.

12. A sorting machine for cans having a pair of exposed metal areas or code marks on the surface thereof comprising a plurality of parallel contact bars, a driven belt adapted to roll said cans longitudinally along the plurality of bars, a chute for conducting the cans along a predetermined path beyond the ends of the contact bars, a gate movable across the chute to divert cans therefrom into a second path, electromagnetic means adapted to operate the gate, an electronic circuit adapted for the production of a signal which will actuate said electromagnetic means, two sources of voltage in said circuit which are in opposition and so balanced as to preclude the circuit producing said signal, a connection from the negative terminal of both voltage sources to one of said contact bars, a connection from the positive terminal of one of said voltage sources to a second contact bar, and a connection from the positive terminal of the secand voltage source to the remainder of the contact bars, whereby, when said first two bars contact the code areas of a can, one source of voltage will be shorted through the can, thereby unbalancing the opposed voltages to cause a signal in said circuit which actuates the electromagnetic means which moves the gate to divert the can from said chute into said second path.

HOWARD J. EMERSON. ROBERT J. O'CONNOR. GEORGE A. EMERY.

REFERENCES CITED 7 The following references are of record in the file of this patent: 

